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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

6 results found.

  1. GRB 070309: Swift-XRT afterglow confirmation
  2. GRB 070309: variability of the XRT afterglow candidate
  3. GRB070309: Swift/XRT possible afterglow detection
  4. GRB 070309: Swift/UVOT Upper Limits
  5. Swift UVOT Finding Charts for GRB 070309
  6. GRB 070309: A long GRB detected by INTEGRAL


Download all Circulars as a .tar.gz archive:
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